ENYO-3012: fix interaction between `-s` & `-p` + use `packagejs:` in `deploy.json`

- the `source:` property of `deploy.json` did not make sense as it was
  always refering  to the  folder where `deploy.json`  is.  it  is now
  replaced by a `packagejs:`  property (default: `"package.js"`) which
  indicates  where   is  the   relative  location  of   the  top-level
  `package.js` from the project root folder.
- only interaction left between `-s|--source` and `-p|--packagejs` is:
  
  > if `--source` is not provided and `--packagejs` is provided, then
  > `--source` is assumed to be the folder containing the given
  > `--packagejs`

- precedence order for `package.js` location is now
  1. from command-line
  2. from `deploy.json` 
  3. default value `"./package.js"`

Enyo-DCO-1.1-Signed-off-by: Francois-Xavier KOWALSKI <francois-xavier.kowalski@hp.com>
ENYO-3012: (less) fix case where `package.js` deep (>1) in the source tree

less-generated assets need to  be referred to from `build/index.html`,
not from the folder where the top-level `package.js` is living.

Enyo-DCO-1.1-Signed-off-by: Francois-Xavier KOWALSKI <francois-xavier.kowalski@hp.com>
ENYO-3012: be more explicit about folders creation during verbose execution

Enyo-DCO-1.1-Signed-off-by: Francois-Xavier KOWALSKI <francois-xavier.kowalski@hp.com>
ENYO-3012: jshint/ tabs+spaces => spaces

Enyo-DCO-1.1-Signed-off-by: Francois-Xavier KOWALSKI <francois-xavier.kowalski@hp.com>
Merge pull request #434 from enyojs/ENYO-3012

ENYO-3012: bad asset path after deploying a non-Bootplate-like Enyo application

Reviewed-By: Ben Combee (ben.combee@lge.com)